Abstract

The larval stages of Battus archidamas, the only Papilionoid butterfly living in Chile, feed on the aerial parts of Aristolochia chilensis. The food material contains aristolochic acids, and so do the insects, which retain these compounds after metamorphosis. The compositions of the acid fractions of plant and herbivore extracts are different, however, indicating selective uptake and/or metabolic transformation by the insect. Aristolochic acids I (I) and Ia (II) are major components of the leaves and tender stems of A. chilensis, while aristolochic acids I (I) and (probably) IVa (III) appear to be the main acid components of B. archidamas imagines. The selective sequestration of aristolochic acids by B. archidamas and other Aristolochia-feeders is discussed.